Spark 2.6.3 disconnecting / not opening


I’m running Spark 2.6.3 on two Windows XP SP2 PCs in a remote location on our domain using a G3 cradle point and VPN conectrator and they keep closing and not reconnecting. If I click on the desktop icon nothing happens, if I reboot the PC it will sometimes work again. I just upgraded the Java to the newest version available version 6 update 29 becasue I thought that was the issue. I was also thinking that the users were logging onto different sessions from different PCs within the domain. For instance a user will work in one location and then drive 30 minutes to the remote location and if they are still logged into Spark on one PC and try to log in again they get kicked out, which was no big deal on the old 2.5 version of Spark.